The Lower Pleistocene, Bathhouse Beach locality, Santa Barbara, California, was examined. The described fauna of molluscs, bryozoans, foraminiferans, ostracods and brachiopods was reviewed and latitude range and depth distributions noted. The bulk of the fauna with perhaps the exception of the foraminiferans occurs off the coast of California today and the affinity of the fauna is decidedly with the Recent Californian rather than with the Aleutian or Panamic provinces.
The cyclostome bryozoan Diaperoecia californica was so abundant in the deposit as to give it the character of a biostrome. The bulk of the sediment in the deposit was carbonate, the remainder silt. The biostrome was in a region of slow sedimentation, away from the shoreline. Its top in 36.6-54.9 m was capped by coralline algae which provided a substrate for the bryozoan.